Conventionally, a steel pipe pile including a helical projection on an outer circumference of a steel pipe and being driven into the ground by rotary penetration has been proposed (see, for instance, Patent Literature 1).
An end of the steel pipe of the steel pipe pile is obliquely cut at a slant angle of 10 to 50 degrees. With the cut region being provided, a pushing-in performance into the ground can be enhanced and a penetration resistance can be restrained, thereby improving an installation efficiency of the steel pipe pile.